Clones were bad because they were unoriginal or boring, people have fave characters then they have fave moves,

my fave character was yoshi, but i like kirbys moves,

but i would have hated if they gave yoshi kirbys moves, it takes away from the range of gameplay, and fun. when you get this game, everyone usually wants to play as each character at least once, because they wanna know whos moves they like the most, it was boring playing the story mode, with a clone becuse it felt like it had been done before, where as a new set of original move, would have made it more fun.

EDIT:
imagine if they did clones in brawl,

there final smashes would be the same, and that would blow my head clean off with anger, it would suck, because its fun to do NEW things

Clones are not good, and if they wanted to do it that way they should just make costumes, or go further and make customizable moove sets, but that would ruin the game, so they should leave every character to a unique individaul move set